T Deletion and D Deletion

Deletion of t sounds and deletion of d sounds occur when we speak fast. Native speakers do not think about t and d deletion; they would typically not notice it.

The deletion of t and d sounds is an aspect of English pronunciation that helps native speakers of English speak more quickly. Some teachers might feel uneasy about teaching deletion because on the surface leaving out sounds would seem to be incorrect. However, in order for one to acheive the closest approximation of natural native speech and to speak at native speaker speed in everyday conversation, it is necessary to take into account T deletion and D deletion.

Sometimes the t sound and the d sound are omitted in English pronunciation. This is called deletion: t and d deletion.
I don't know - "becomes I don' know" - t is often deleted after an "n" sound in a contraction

mountain - becomes moun'ain - t is deleted after "n" in certain words
In the word "twenty", the second t sound is often left out when speaking quickly.

"wanna" and "gonna" - These are two very typical reductions used in everyday speech. There's a kind of t deletion here, as "want to" becomes "wanna". The "a" in "wanna" represents the schwa vowel sound in the word "to". The same thing can be said of "gonna", except for with "gonna", the nasal final "g" sound is also deleted.

Deletion also occurs in certain phrases throughout our speech when we speak quickly.

Example: I need to wake up extra early tomorrow - becomes "I nee təwake up extra early tomorrow. - The d sound is often deleted when we speak fast.

In the word "and", "d" is often deleted, and the "a" becomes a schwa vowel sound.

Example: black -n- white photograpahs

Other instances of t deletion occur in the words "left" and "just". It's on the left side - becomes "it's on the lef' side.